Last updated on .From the section Brentford
The English premier league club agreed a fee for the 20-year-old with Bologna, who is close to moving to Brentford.
The former Heart of Midlothian defender is finalising his terms.
In March, he made his Scotland debut after a strong performance in Italy.
There are add-ons to the deal that could make it worth more than 17 million dollars.
The fee for his transfer two years ago to the Italians is expected to be reduced by Hearts.
Before he joined Sinisa Mihajlovic's side, he had only played 33 times for Hearts.
Bologna finished 13th of the 20 teams in Italy's top flight last year, but he played in all but two of them.
After opting out of selection for the Scotland Under-21s before being called up to the senior squad, he has been linked with a move to a top-flight rival.